Question: Simplify the following expression: $a = \dfrac{2z + 5}{z + 5} \div 2$
Answer: Dividing by a number is the same as multiplying by its inverse. $a = \dfrac{2z + 5}{z + 5} \times \dfrac{1}{2}$ When multiplying fractions, we multiply the numerators and the denominators. $a = \dfrac{(2z + 5) \times 1} {(z + 5) \times 2}$ $a = \dfrac{2z + 5}{2z + 10}$